New Aviation Weather Services Book

[Maxed-out]

You might want to check out the new Aviation Weather Services book (AC 00-45H) that was made available (draft copy) on the internet recently. The NWS personnel have been busy. More than a few changes coming soon. The NWS is definitely leaning towards reducing the amount of textual products available in favor of Web-based graphical products. So far, I've noticed they're planning on phasing out the Weather Depiction Chart, Constant Pressure Chart and Area Forecasts in favor of various graphical products available on the net. Also noticed that PIREPS will have a new friend called an AIREP. I'm sure there's more. Here's the link to the book:

https://www.faa.gov/aircraft/draft_docs/media/afs/AC_00-45H_Coord_Copy.pdf

Also found an example of the new Graphical Forecasts for Aviation product that will replace the textual Area Forecast. Very interesting.

http://new.aviationweather.gov/areafcst

 

[MAKG1]

Egads. That's a bunch of TAFs, not at all a substitute for an area forecast.

What are the forecasted cloud tops? That's an essential bit of area forecast information you don't get from any of the other official products.

What an FN mess. AWC needs someone who knows how to display areal or volumetric information. That thing is terrible. NCAR used to be pretty good at this….

 

[Maxed-out]

Here are the direct quotes from AC 00-45H about he Weather Depiction Chart and the Constant Pressure Analysis. Since this is a draft copy I'm looking at, I suppose that both of these statements could be errors, but it sure doesn't read like that.

4.2.2 Weather Depiction Chart. The Weather Depiction Chart (see Figure 4-18, Weather Depiction Chart—Example) is being phased out by the NWS, in favor of newer ceiling and visibility products, like the CVA product.

Constant Pressure Analyses. Constant Pressure Charts (see Figure 4-20, 500 MB Analysis Chart— Example) are being phased out by the NWS in favor of other products (see Figure 4-21, 500 MB Height, Temperature, and Wind, 00-hour Forecast (i.e., Model’s Analyses from the NWS’s North American Model [NAM] Example)) available on NCO’s Model Analyses and Guidance Web site. See subparagraph 5.14.1 for additional information.

 

[Maxed-out]

For those of you with more knowledge on this subject than me, please explain the following:

If you fly to locations that don't have TAFs, then you have probably used the Area Forecast to determine forecast weather (ceilings and vis.) at your ETA, at your destination. To satisfy the regulations, you need to determine whether you need an alternate (or not) for your destination (1-2-3 reg.). You also need to determine what the forecast weather is, at your ETA, at the alternate (600-2, 800-2) to determine if it qualifies as an alternate.

Correct me if I'm wrong, but so far, (assuming conventional Area Forecasts are no longer available), none of the listed weather forecast products in the new AC 00-45H (besides the TAF, which my destination doesn't have), gives me a forecast of specific ceilings and visibilities at ETA.

These weather forecast products (described elsewhere in this document), to be consulted in lieu of the FA, together provide information similar to that found in the FA. The information often is in greater resolution and with the added benefit of graphical depiction. They include:

• Significant weather (SIGWX) charts (see subparagraph 5.16),
• Aviation forecast discussions (see subparagraph 5.19.1),
• Terminal aerodrome forecasts (TAF) (see subparagraph 5.10),
• AIRMETs (see subparagraph 5.2),
• National digital forecast databases (see subparagraph 5.19.2),
• Cloud top height forecast graphics (see subparagraph 5.19.3), and
• Cloud layer products (see subparagraph 5.19.4).

I'm probably missing something, so forgive the ignorance. It's all new to me. It's probably in the new NDFD database graphic, but I haven't found it yet.

 

[PPC1052]

Take some time to actually look at the tool before you completely dismiss it. Cloud tops are there.

I am dense and don't see them.

 

[MAKG1]

Take some time to actually look at the tool before you completely dismiss it. Cloud tops are there. I like how they integrate and overlay the complementary elements. When you choose turbulence, for example, all the pertinent turbulence information is presented including G-AIRMETs or SIGMETs for turbulence, turbulence pilot weather reports and GTG. Same with icing. You can further configure what you want to see or not see.

You have to remember that this is Version 1.0 of the product that was largely created by a developer at NCAR. There's a survey in the upper right. Send in your constructive comments if you don't like what you see.

What makes you think I didn't?

The cloud depiction makes a distinction between above 18000 and below. That's nice, but not very useful for a pilot of an airplane that won't make it to 18000.

The current FA will tell me forecasted ceilings and cloud tops, at least at even thousands. It makes a difference if the tops are 6000 vs 8000 as local freezing levels are around 8000 right now.

Graphical depictions are much more useful than text for large area information. But it's important not to lose capability entirely.

 

[Maxed-out]

Thanks scottd. So much new stuff out there, I figured I was missing something.

 

[PPC1052]

From the menu on this page, select Weather. Then select Clouds from that dropdown menu. This will show the RAP Cloud Fractions markers on the map. Click on one of those markers to see cloud tops and bases for that area. Make sure you pick one that's not showing clear to see an example.

Awesome. Thank you!

In my opinion, this makes cloud top informaiton much easier to find.

 

[MAKG1]

If you had looked at this more carefully you would have noticed that the RAP Cloud Fraction Composite markers are where you will find the bases and tops...it's not just making a distinction of what's above and below 18,000 ft. Like any GIS interface such as this, the markers are decluttered the further you are zoomed out. Just saying...

A comment I made to the AWC is that these markers need to be coincident with airports, not using a RAP grid. Sure, you can zoom way in to the map and find a marker that is reasonably close. But I'd rather see it interpolated to airports.

A graphical depiction of cloud tops would be a lot more useful than poking everywhere you might possibly need to know along a route.

Too much hidden stuff. That it's that easy to miss is a problem.

In the field, we call this "expert friendly." It's fine if you know and train all your users. It's not fine for the public.